Cole was shown a straight red card for a challenge on Gunners debutant Laurent Koscielny just before half-time in the match which ended 1-1 but the Frenchman says he could not see the incident clearly and questioned whether Cole was capable of a tackle that could have left his opponent with a broken leg.
"It was completely in the corner and I was on the bench, so I couldn't see it," Wenger said.
"But Joe Cole is usually a fair player, he is not one I would record is a guy who tries to hurt people. It is not his style.
"Maybe he was a bit rushing in his tackle. He kicked him - certainly accidentally - well because he [Koscielny] had a big knock on his shin.
"Fortunately his shinpad protected him well.
"We were scared it was broken because when he was moved off the pitch the physio told me it could be broken."